Air conditioning system



June 6, 1939. N. PASSUR AIR CONDITIONING SYSTEM Filed Oct. 25, 1937 INVEN TOR.

A TTORNEYS.

BY fv Patented June 6, 1939 UNITED STATES PATENT OFFICE AIR CONDITIONING SYSTEM Norman Passur, Oakland, Calif.

Application October 25, 1937, Serial No. 170,817

6 Claims. (01. 62-6) The present invention relates to air conditionin: systems of the type in which ice is used as the cooling agent and water as the circulating cooling medium.

'5 The principal object of the invention is to provide increased efliciency in the use of ice, whereby less ice is required to produce a given amount of cooling. A second object is to prevent unnecessary waste of water. Still further objects and advantages of the invention will become apparent in the following specification which should be read with the understanding that the form,

construction and arrangement of the various parts may be varied within the limits of the claims 1 be used in other applications without material change.

The'figure of the drawing herein is a diagram charged into the car by the fan 29. The path of illustrating the relative arrangement of and connections between the various elements constituting the entire system.

The reference numeral I designates an ice tank, which, in railway car installation, is positioned preferably beneath the floor 2 of the car. A grate or ra'ck 3 is provided in the tank i upon which blocks of ice 4 are supported, and below said grate the bottom 5 of said tank slopes downwardly toward an outlet pipe 6 which leads to a Water storage tank 1. Both the ice tank I and the water tank 1 contain water during the operation of the system, the maximum level of said water, as indicated by the broken line 8, being determined by an overflow outlet 9 in the upper portion of the water tank.

The ice tank I has a second outlet pipe I 0 which leads through a check valve H to' a water circulating pump l2, driven preferably by an electric motor i3. The discharge pipe M of said pump conducts the cold water to an absorber prefer- 45 ably in the form of a coolingcoil l5 hereinafter referred to as the auxiliary cooler. From said absorber the water returns through a. pipe It to the ice tank I.

The water storage tank I has an outlet pipe 0 ll leading from its ;lower portion, which conducts the water through a check valve I8 to a second pump l9 driven preferably by an electric motor 20. The discharge pipe 2| of said second pump l9 leads to an absorber preferably in the 55 form of a cooling coil 22, hereinafter referred to as hereto appended, without departing from the spir the pre-cooler, from which the water returns through a pipe 23 to the water storage tank I.

A branch 24 of the pipe 2| leads to a spray nozzle 25 in a washer 26. The water sprayed within said washer is caught by a pan 21 in the bottom 5 thereof, and returns to the water storage tank I through a pipe 28. The washer 26 thus functions as an absorber in parallel with the coil 22. Said coil 22 may, .if desired, be omitted, the entire 7 pre-cooling effect being provided by the washer 26. 10

The pre-cooler 22, the washer 26, and the auxilliary cooler I5 are arranged in a unit structure, preferably above the floor 2 of the car, so that air is drawn through them by a fan 29. A steam radiator 30, through which steammay be passed from 5 suitable steam pipes 3| when heating rather than cooling is desired, is included in the system. Air enters through the pre-cooler 22, thence passes through the washer 26 where it is cleaned, humidified and deodorized by the Water spray, I0 thence through the heating radiator 30, thence through the auxiliary cooler l5, and is again disthe air is indicated by the large broken line arrows in the figure. 5

Separate thermostats 32 and 33 suitably positioned within the car, control the respective pump motors l3 and 20. The electric circuits necessary to operate and control said motors are common and well known in the art, and are not illustrated in the diagram, the connecting lines 34 and 35 between the thermostats and said motors merely indicating that each motor is individually controlled by its own thermostat.

In operating the apparatus, ice is placed within the tank I, and sufficient water is added to permit circulationin the two systems, Without necessarily filling both the ice tank I and the water storage tank I. The thermostat 33, controlling the pre-cooler pump I9, is set to operate at slightly lower temperatures than the thermostat 32 which controls the' auxiliary cooler pump I2. Therefore, as the temperature of the car rises, the pre-cooler pump l9 begins to operate first circulating water from the storage tank I through the pre-cooler 22 and washer 26,'said water returning to said storage tank. Under mild weather conditions, such operation of the precooler and washer are usually sufficient to mainis lost through the overflow 9 until sufiicient melting has occurred to fill both tanks.

However, if the temperature of the car continues to rise during operation of the pre-cooler and washer, the thermostat 32 starts the auxiliary cooler pump 82, which circulates water from the ice tank I through the auxiliary cooler l5 and back to said ice tank. The auxiliary cooler l5 being larger than the pre-cooler 22, and the water therein being circulated directly over the ice, the temperature of the car is rapidly lowered ,to such a point that the thermostat 32 shuts off the auxiliary cooler pump I2. The pre-cooler pump [9 continues to operate however until the car temperature falls still further.

When the auxiliary cooler is operating, the ice melts more rapidly, raising the water level, caus-.

ing cold water to flow from the ice tank to the water storage tank, and discharging warmer Water from the outlet 9. This reduces the temperature of the water insald storage tank, and increases the cooling efiect obtained from the precooler.

It Will be seen that the invention'contemplates the use of two functionally independent circulation systems, one containing both ice and water, and having greater cooling capacity, and the other containing water'only, and having less cooling capacity. The water in the second or precoolingsystem issupplied initially and replenished more or less continuously from the first system, and to that extent is cooled by the ice. The water in the pre-cooling system operates at a higher temperature than the water in the auxiliary cooling system, and since the only water discharge for both systems is through the overflow 9 of the pre-cooling system, the water lostthrough said discharge is necessarily at comparatively high temperature, i. e. a temperature only slightly below the air temperature maintained in the car. Thus the greatest possible efiiciency and the least possible loss of water are obtained.

The pre-cooling system operates through a much longer cycle than the auxiliary cooling system. As before stated, under conditions of mild temperature, the auxiliary system may not operate at all, but the pre-cooling system will operate almost continuously. This provides almost continuous circulation and washing of the air in the car, removing odors and dust therefrom, with very little melting of ice and loss of water.

It will be apparent that certain elements of the two system may be combined without afiecting the independent functioning of said systems. Thus for example, a single pump with a suitable selective control valve may be substitutedfor the two separate pumps hereinbefore described, and a single absorber, with'suitable connections from and to the two tanks, may be substituted for the two separate absorbers. Such variations, being obvious to those skilled in the art, have not been illustrated herein.

I claim:

1. In an air conditioning system, a tank containing both ice and water, a second tank con taining water, means for supplying the second tank with water from the first tank, an absorber connected with the first tank, a second absorber connected with the second tank, means for circulating the water from said tanks independently through their respective absorbersand returning it independently to said tanks, and means for passing the air to be conditioned over said absorbers.

2. In an air conditioning system, a tank containing both ice and Water, a second tank containing water, means for supplying the second tank with water from the first tank, an absorber connected with the first tank, a second absorber connected with the second tank, a washer connected with the second tank, means for circulating water from the first tank through "the first absorber, and means for circulating water from the second tank through the second absorber and said washer, all of said water being returned independently to'the respective tanks, and means for passing air over said absorbers and through said washer.

3. In an air conditioning apparatus, a closed circulating system including an absorber and storage means containing ice and water, a second closed circulating system including a second absorber of less capacity than the first absorber and storage means containing water, means'for transferring cold water from the first system to the second system, means for circulating the water in said systems, means for passing the air to be conditioned over said absorbers, and means responsive to the temperature of the conditioned air for selectively controlling said circulation, the

first system operating at higher air temperatures than the second system.

4. In an air conditioning apparatus, a closed circulating system including an absorber and storage means containing ice and water, a second closed circulating system including a second absorber, a washer, and storage means containing water, means for passing the air to be conditioned oversaid absorbers and through said washer, means for transferring cold water from the first system to the second system, means for circulating the water in said systems, and means resp0n sive to the temperature of the conditioned air for selectively controlling said circulation, the first system operating at higher air temperatures than the second system.

5. In an air conditioning apparatus, two closed water circulating systems, each system including heat absorbing means and one system including means for storing ice, a connection between said systems for transferring cold water supplied by the melting of said ice in one system to the other system, means for discharging warmer water. from said other system as said melted ice water is supplied to it, means for circulating the water in each system, means for separately controlling the circulation in said systems, and means for passing the air to be conditioned over said heat absorbing means.

. 6. In an air conditioning system, a tank containing both ice and water, a second tank containing water, a connection between said tanks positioned to supply cold water from the lower region of the first tank to the second tank, an absorber connected with the first tank, a second absorber connected with the second tank, means for circulating the water from said tanks independently through their respective absorbers and returning it independently .to said tanks, and means for passing the air to be conditioned over said absorbers.

NORMAN PASSUR. 

